feat(step8): 外部模型从单文件升级为母文件夹多模型字典扫描

src/gui/core/worker_thread.py

@@ -326,6 +326,14 @@ class WorkerThread(QThread):
         method_name = step_method_map[step_name]
         step_config = dict(config.get(step_name, {}))
 
+        # 透传面板顶层传入的外部预训练模型（GUI step8_panel 通过 config['_external_model'] 传入）
+        # 非空才覆盖（遵循 feedback_never_overwrite_with_empty 原则）
+        for key in ('_external_model', '_external_model_path',
+                    '_external_models_dict', '_external_model_dir'):
+            val = config.get(key)
+            if val is not None and val != "":
+                step_config[key] = val
+
         step_config['skip_dependency_check'] = True
 
         if step_name == 'step9':